Why some marijuana growers are getting into salad greens

Today, Gallagher is one of an
increasing number of hydroponic growers who have transitioned from
mari­juana to produce. “I like to grow anything anyone tells me can’t be
grown hydroponically,” he says. “Watermelons. Hops was a good one; no
one believed it was possible.”

Hydroponic farming is booming, along with other forms of
“controlled-environment agriculture.” Because indoor operations use up
to 90 percent less water than outdoor farms, don’t have to use many
pesticides, and can grow a large volume of food in a relatively small
space, they’ve become popular with sustainability-minded restaurants and
grocery stores. But as recently as ten years ago, growing fruit and
vegetables inside didn’t make sense in the U.S. market. While the
practice has long been central to the Dutch and Japanese food systems,
in the U.S., the relatively cheap cost of land and water and the high
cost of lighting and indoor growing systems combined to make hydroponics
too expensive for anything but a high-value cash crop like marijuana.

Today, thanks in part to the cannabis industry, that calculus has
changed. Marijuana growers have refined hydroponic technology in ways
that have driven down the price. Meanwhile, the cost of land and water
has gone up, and consumers have become more willing to pay a slight
premium for local, sustainable produce. Given that “tomatoes” is a code
word for “weed” in hydroponic supply stores, it’s fitting that nearly 50
percent of the country’s actual tomatoes are now grown indoors.